DatabaseHelper.kt

class DatabaseHelper private constructor(context: Context) {
    companion object {
        private var instance: DatabaseHelper? = null
        fun getInstance(context: Context): DatabaseHelper {
            if (instance == null) {
                instance = DatabaseHelper(context)
            }
            return instance!!
        }
    }

    private val database: SQLiteDatabase = context.openOrCreateDatabase("app_db", Context.MODE_PRIVATE, null)

    fun executeQuery(query: String) {
        database.execSQL(query)
    }

    fun getData(query: String): Cursor {
        return database.rawQuery(query, null)
    }
}

val databaseHelper = DatabaseHelper.getInstance(applicationContext)
val cursor = databaseHelper.getData("SELECT * FROM users")